https://www.aliexpress.com/item/Upgrade-real-leather-Cushion-ear-pads-seal-for-Sennheiser-HD800-HD800S-Headphone/32845611215.html - Even if you choose EMS (+$20) , it will get to the US within about a week or 2 at the most.

I just realized that, after i posted the question. Thanks for replying though. Much appreciated. Staying in Singapore, the aliexpress links (except it does not have the hybrid/Fenestrated Sheepskin options) is much cheaper for me compared to the ones from massdrop.

I am sure they are not, just as they are not saying they are...and just like you are not saying your not Sennheiser pads.

Its a pair of ear pads dude.. after all, its a pair of foam enclosed by some fabric or leather. they can't make it look like a tea pot... So wheres the knockoff? At most, one can say you inspired their design...

It's not that I don't get the urge calling them 'knock-offs'. But a simple and niche-within-a-niche product like this, its does not justify yourself as the original either...

It all comes down to how much people value the 'Dekoni' brand name for a low tech content product like this.

As for how much of a difference does it make for using a 'better' foam or enclosure is subject to questions.

FYI, its nice to have those measurements done. Its just something as close as one can expect for something like this before actually trying them. But ultimately, the very definition of frequency response charts and their interpretations are flawed and without industrial standards...

Eh, not sure about low tech. Within the closed system of a headphone, the earpads play a fairly large role in the headphones tuning. While the two may look the same, what is on the inside may be different. Beyond that you also have to consider reliability, support (warranty), and if the products are ethically sourced (if that is important to you). This isn't to say one is better than the other, just that differences between the two may very well be audible.

I've sold my HD800, and had replaced the pads on those with a fresh set from Sennheiser at one point. If I still had them and needed to replace the pads, I would go the same route as before.

My argument being, anyone can take the so called "knock off's" and slap them inside a fancy box.

On a serious note, comparing the ones from Aliexpress to the "Dekoni" ones, there was literally 0 difference. They look the same, feel the same, compress the same, glue used seems to be the same and the material feels/looks exactly the same. So there is that.